In the field of health care mobility and transportation of vibration sensitive or heavy duty devices, there is a need for wheelchairs, gurneys, stretchers, and equipment carts with wheels which will traverse obstacles while minimizing vibration and excessive impacts.
Patient transport devices such as wheelchairs, gurneys and stretchers may cause discomfort or damage to the occupant during transport over obstacles due to transmission of wheel shocks throughout the mobility device. It is a common occurrence for a wheelchair user to be pitched out of the chair and potentially injured due to an obstruction or irregularity in the pathway. Vibration in the frame of a medical mobility device may cause lower back pain or may trigger spasms in some patients. Hospitals, laboratories, funeral homes, photographers or anyone that requires decreased vibration in a rolling castered device has a need for a suspension system which will absorb or reduce transmission of wheel vibration and deflection to the transported person or goods.
Current casters and suspension systems for wheelchairs, gurneys and other carts and vehicles fail to provide satisfactory shock absorption for the vehicle. There have been attempts to place a steel spring around the stem bolt of the caster assembly in order to accomplish wheel shock absorption. This only allows the wheel to move vertically and does not effectively reduce vibration during forward motion.